Peterbilt / 6NZ Vibration

it could be the harmonic balancer on the crankshaft going bad too

 

My vote is for the ride height.

 

Could also be a driveshaft 'out of phase'... they WILL twist if you have a tough time sliding an axle...

But I'd agree that ride height is a major suspect... I'm dealing with that right no since I changed my air leveling valve...

 

Nope, have not invested in those.
Thanks

 

I check mine like u-joints except u joints should NOT have any play where a carrier bearing will have very little since it is a rubber bushing in it./

Thats the way I was always told from and ol school mechanic. right or wrong it has worked for me.

 

Wonder what the exact ride height for 200 379 should be?

 

Jay , if you have the regular air-leaf its 11inches on the rear and 9.5 on the front drive-measure from the bottom of the frame i beam to the top of the bottom plate that holds the airbag in place

 

I actually called Rush in Nashville and the service guy said he could guess because they have a special tool for it now, but start at 11 3/4 inches from bottom of frame rail to bottom of air bag. test it and if its still vibrating adjust 1/4 inch at a time.

I have the Low Air Leaf.
Thanks

 

found the operators manual for my truck. It says in there for low air leaf i should set height at 15.88 inches not 11 3/4. so i did it today haven't had time to test drive. It was at 15 so i do not think its gonna make a big difference

 

Jay,

Keep in mind Pete has several different suspensions. Here ya go:

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